DALLAS, United States (AFP) — Spain Captain Rodri warned Portugal on the eve of Monday’s World Cup last-16 clash that the European champions can still get a lot better.

Spain, one of the favourites in North America, were held to a shock 0-0 draw with debutants Cape Verde to open their title charge.

They then beat Saudi Arabia 4-0 and Uruguay 1-0 to top their group, before a statement 3-0 win over a dogged but limited Austria in the last 32.

That performance served notice to their rivals, and ‘midfield general’ Rodri said that was just the start.

“Spain’s evolution [at the tournament] has been gradual,” the 30-year-old Manchester City ace told reporters on Sunday ahead of the meeting with Cristiano Ronaldo’s Portugal in Texas.

“Obviously in a sense that is normal — in the first games you try to adapt to a different environment, different pitch, different type of teams you face, it is never easy.

“So I think in a gradual way, always growing and always knowing that the big things are coming now.”

Spain’s goalless stalemate with Cape Verde came as a huge surprise, but Rodri said, “We didn’t lose our heads, we stayed calm, and I think right now we still have a big gap of improvement.”

Rodri, who has been heavily linked with a move back to Spain, with Real Madrid, said “details” will decide the winner at the home of the Dallas Cowboys.

“I think whoever is able to be more clinical, whoever is able to bring more intensity, more aggressiveness, play more in the opponent’s half, I think will win,” he said.

Spain and Portugal both have squads packed with quality, especially in midfield.

But Luis de la Fuente’s 2024 Euros winners go into a tantalising showdown as favourites.

Rodri’s fellow midfielder Mikel Merino, an English Premier League winner with Arsenal, said the tournament had shown that nothing could be taken for granted.

“I see a real competition where every national team is ready to face the opposition, you see big names, big national teams are struggling or suffering against teams that are supposedly lower,” he said ahead of a final training session.

“This shows us that the respect we have to have for every opponent is massive.

“Hopefully we can win tomorrow and keeping making history with our national team.”

Spain lifted the World Cup for the first time in 2010, but then shockingly went out in the group stage four years later.

In 2018 and 2022 they exited prematurely, in the last 16.